{"id":77,"date":"2020-04-08T15:01:57","date_gmt":"2020-04-08T15:01:57","guid":{"rendered":"https:\/\/thechemicalelements.com\/?page_id=77"},"modified":"2023-08-16T10:03:31","modified_gmt":"2023-08-16T10:03:31","slug":"niobium","status":"publish","type":"post","link":"https:\/\/thechemicalelements.com\/niobium\/","title":{"rendered":"Niobium (Nb)"},"content":{"rendered":"
\n
\"\"<\/figure><\/div>\n\n\n

Niobium is a chemical element with atomic number 41 in the periodic table. It\u2019s the most plentiful metal found in Earth\u2019s crust. Being a member of the transition metals family of periodic table elements, this superconductor can have 2, 3, or 5 electrons in the outermost valence shell that play a part in the chemical bonds of niobium with the other elements.<\/span><\/p>\n\n\n\n

Named after the Greek goddess of tears, niobium is classified as one of the five major refractory metals. Element 41 also displays paramagnetic properties and superconductivity in the presence of strong electric currents and magnetic fields.\u00a0<\/span><\/p>\n\n\n\n

<\/div>\n\n\n\n

Chemical and Physical Properties of Niobium<\/span><\/h3>\n\n\n\n
Property<\/strong><\/td>Value<\/strong><\/td><\/tr>
The symbol in the periodic table of elements<\/td>Nb<\/td><\/tr>
Atomic number<\/td>41<\/td><\/tr>
Atomic weight (mass)<\/td>92.91 g.mol-1<\/td><\/tr>
Group number<\/td>(Transition metals)<\/td><\/tr>
Period<\/td>5 (d-block)<\/td><\/tr>
Color<\/td>Lustrous white; also commonly found in blue, green, and yellow<\/td><\/tr>
Physical state<\/td>Solid metal at room temperature<\/td><\/tr>
Half-life<\/td>From less than 44 nanoseconds to 20.300 years<\/td><\/tr>
Electronegativity according to Pauling<\/td>Unknown<\/td><\/tr>
Density<\/td>8.4 g.cm-3 at 20\u00b0C<\/td><\/tr>
Melting point<\/td>2477\u00b0C, 4491\u00b0F, 2750K<\/td><\/tr>
Boiling point<\/td>4741\u00b0C, 8566\u00b0F, 5014K<\/td><\/tr>
Van der Waals radius<\/td>0.143 nm<\/td><\/tr>
Ionic radius<\/td>0.070 nm (+5) ; 0.069 nm (+4)<\/td><\/tr>
Isotopes<\/td>36<\/td><\/tr>
Most characteristic isotope<\/td>Niobium-93<\/td><\/tr>
Electronic shell<\/td>[Kr]4d45s1<\/td><\/tr>
The energy of the first ionization<\/td>652 kJ.mol-1<\/td><\/tr>
The energy of the second ionization<\/td>N\/A<\/td><\/tr>
Discovery date<\/td>In 1801 by Charles Hatchett<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

With the periodic table symbol Nb, atomic number 41, atomic mass of 92.91 g.mol<\/span>-1<\/span>, and electron configuration [Kr]4d<\/span>4<\/span>5s<\/span>1<\/span>, niobium is soft and ductile paramagnetic metal. It reaches its boiling point at 4741\u00b0C, 8566\u00b0F, 5014K, while the melting point is achieved at 2477\u00b0C, 4491\u00b0F, 2750K. Despite the high melting point, niobium has a lower density than the other refractory metals. Niobium\u2019s atomic radius according to van der Waals is 0.143 nm, while its electronegativity according to Pauling is unknown.<\/span><\/p>\n\n\n\n

Element 41 has a cubic crystalline body-centered structure and 2, 3, or 5 valence electrons. At extremely low (cryogenic) temperatures, this transition metal adopts superconducting properties in the presence of strong electric currents and magnetic fields. Being corrosion-resistant, niobium metal starts to develop the protective oxide film at a temperature of 200oC. The thickness of its oxide layer determines the color of the metal niobium, which can vary from white to blue, yellow, and green.<\/span><\/p>\n\n\n\n

<\/div>\n\n\n\n

How Was Niobium Discovered?<\/span><\/h2>\n\n\n\n

The English mineralogist and analytical chemist Charles Hatchett (1765 \u2013 1847) had performed numerous analytical researches on many types of minerals and ores in his private laboratory. By examining the mineral samples exposed in the British Museum, Hatchett\u2019s interest was caught by a particular sample for which he believed contains a new, undiscovered substance.  <\/span><\/p>\n\n\n\n

More than a century before Hatchett\u2019s revolutionary chemical trial, the mineral sample that was an object of scientific interest to the English chemist was taken from a type of American ore and sent to England by John Winthrop the Younger. At the time, Winthorp was the first governor of Connecticut, United States. Originating from North America, the mineral sample was labeled <\/span>columbite, <\/span><\/i>in honor of the American continent discoverer, Cristopher Columbus. <\/span><\/p>\n\n\n\n

That special day in 1801, Hatchet was analysing the aforementioned mineral sample obtained from the British Museum. This English chemist attempted an experiment in which he heated a mineral sample with potassium<\/a> carbonate. After that, he dissolved the resulting product in water, added acid to it which led to a precipitation. <\/span><\/p>\n\n\n\n

The outcome of Hatchett\u2019s experiment discovered a new chemical element which was classified under the atomic number 41. Charles Hatchett named the new element <\/span>columbium<\/span><\/i>, as assigned the symbol Cb to the substance he discovered.<\/span><\/p>\n\n\n\n

In 1864, Swedish scientist Christian Blomstrand succeeded in isolating the metal niobium by reduction of chloride exposed to heat in a hydrogen<\/a> atmosphere.<\/span><\/p>\n\n\n\n

<\/div>\n\n\n\n

How Did Niobium Get Its Name?<\/span><\/h2>\n\n\n\n

Almost half a century after Charles Hatchett discovered columbium, the German chemist Heinrich Rose managed to independently prove that the columbium contains not one, but two new substances that were extremely hard to tell apart – tantalum<\/a> and niobium. <\/span><\/p>\n\n\n\n

Rose\u2019s name choice of the new substance came from the fact that it shares many chemical and physical properties with tantalum, the element classified right above the niobium in the periodic table. This was also the reason why it was so difficult for the scientists to distinguish these two elements. <\/span><\/p>\n\n\n\n

The mythical side of this story relates the name <\/span>niobium<\/span><\/i> to the Greek goddess of tears, Niobe. Namely, she was the daughter of Tantalus – the son of Zeus and the nymph Plouto in the Greek mythology, to whom all things were elusive and \u2018<\/span>tantalising<\/span><\/a>\u2019. <\/span><\/p>\n\n\n\n

In this way, Heinrich Rose wanted to symbolically mark the scientifically proven similarities between the two new elements – niobium and tantalum. <\/span><\/p>\n\n\n\n

The International Union of Pure and Applied Chemistry (IUPAC) officially approved the name niobium in 1950.<\/span><\/p>\n\n\n\n

<\/div>\n\n\n\n

Where Can You Find Niobium?<\/span><\/h2>\n\n\n\n

Niobium is mainly mined from pyrochlore deposits, after which it\u2019s transformed into the niobium pentoxide Nb<\/span>2<\/span>O<\/span>5<\/span>. For commercial purposes, this chemical element is typically obtained from the mineral columbite as the main source. <\/span><\/p>\n\n\n\n

The locations rich in niobium mineral ores can be found worldwide. However, the most active niobium ore mines are located in:<\/span><\/p>\n\n\n\n